Just a place to play around and test code

The question of determining the world's largest cities does not allow a single, simple answer. It depends on which definitions of "city" and "size" are used, and how those definitions are applied.

The "size" of a city can refer to either its land area or, more typically, its population.

The borders of a city can also be defined in any of several ways:

"City" defined as a physically contiguous urban area, without regard to territorial or other boundaries.

"City" as defined by the habits of its demographic population, as by metropolitan area, labor market area, or similar. Such definitions are usually based on commuting between home and work.

"City" as strictly defined by a given government (city proper). Typically based on a municipality or equivalent entity, or sometimes a group of municipalities under a regional government.

Cities making the top 20 in a list

The numbers after each cell give the ranking of that city in that list.